Tetraalkoxysilane is used as a raw material for manufacturing various silane compounds, organic silicone polymers, various silylating agents, colloidal silicas, and ceramics.
A common method for producing industrially alkoxysilanes is a method in which natural silicon dioxide as a starting raw material is mixed with carbon and then reduced at high temperature to yield metal silicon, which is then made to react with chlorine to produce tetrachlorosilane, followed by a further reaction with alcohol (See PATENT DOCUMENT 1.). Other methods are also known in which metal silicon is reacted directly with alcohol (See PATENT DOCUMENTS 2 and 3.).
All of these methods, however, must undergo a process of producing metal silicon which requires high temperature, and therefore, they are problematic owing to the poor energy efficiency.
On the other hand, methods of producing alkoxysilane directly from silica are known wherein silica is reacted with an alkyl carbonate with the aid of an alkali metal element or an alkaline earth metal element as a catalyst, to produce alkoxysilane (See PATENT DOCUMENTs 4 and 5.). While these methods do not use metal silicon as a raw material, and therefore, are advantageous in energy efficiency, they require an alkyl carbonate, a relatively expensive compound, fed in a molar quantity stoichiometrically at least twice as much as silica, and therefore, are problematic as an industrial method for producing tetraalkoxysilane.